April 19, 2005

Daily Aspirin, Ibuprofen Cut Smokers’ Oral Cancer Risk

HealthDay News -- Smokers who've tried but failed to kick their habit may want to pop a daily aspirin, ibuprofen or naproxen (Aleve) to help cut their risk of mouth cancer, new research suggests.

Previous studies have shown this family of non-steroidal anti-inflammatory drugs (NSAID) effective in preventing other cancers, and the same may now be true for oral malignancies.

"NSAIDs approximately halves the risk of [these] cancers in smokers," said lead researcher Dr. Jon Sudbo, of the Norwegian Radium Hospital in Oslo.

It's not clear whether daily NSAID use can also reduce risks for the No. 1 cancer killer of smokers, lung cancer, however.

"We will try and answer that question in the near future," Sudbo said.

In their study, presented April 18 at the annual meeting of the American Association for Cancer Research, in Anaheim, Calif., Sudbo's team looked through a Norwegian cancer database to compare daily NSAID use by more than 900 adults with a long history of tobacco use.

Half of the group had been diagnosed with some form of mouth cancer, while the other half had not.

They found that smokers who had taken a daily NSAID (such as aspirin, ibuprofen or naproxen) for at least six months were 65 percent less likely to develop oral malignancies than smokers who had not. Reductions in risk for oral cancer fell as years of NSAID use increased, the researchers add.

Those benefits were not found in long-term users of a non-NSAID pain reliever, acetaminophen (Tylenol), however. That suggests that something about NSAIDs, in particular, is working to ward off mouth cancer.

Dr. Raymond N. DuBois, a professor of cancer biology at Vanderbilt University, said he isn't surprised by the findings.

"There's a lot of data out there on reductions in risk for gastrointestinal cancer, esophageal and gastric and colorectal cancer" connected to long-term NSAID use, he pointed out. "Usually people who take NSAIDs on a regular basis have about a 40 to 60 percent reduction in risk."

This study is interesting, however, he added, in that it suggests that NSAIDs can protect against cancer even in the presence of a strong carcinogen such as tobacco.

"So, if you cut out smoking as a variable, would you get an even better reduction with NSAIDs?" DuBois wondered.

He said these drugs probably fight malignancy by inhibiting chemicals responsible for chronic inflammation. "That's a kind of smoldering state that makes cells more prone to develop into cancer," he explained.

Both Sudbo and DuBois cautioned, however, that long-term NSAID use comes with some level of cardiovascular risk, so smokers should talk to their doctors before embarking on any course of therapy.

The Norwegian study also found a threshold effect, in terms of the types of smokers helped by NSAIDs. Specifically, individuals who had smoked for "30 or less pack-years" benefited most from a daily pill. According to the researchers, 30 pack-years would equal a two-pack-a-day, 15-year habit or a 30-year, one-pack-a-day habit. Smokers with even longer or heavier smoking histories reap much less of a protective effect from NSAID use, the researchers found.

Of course NSAIDs are certainly not the best answer to helping smokers avoid cancer.

The real solution: "Quit smoking," said Sudbo.

DuBois agreed. "It's really a no-brainer, of course, but a lot of people are struggling with it," he said. "Still, we know that if smoking is taken out the picture, the risk goes down dramatically."